“…Synthesized according to 7 Redish-brown solid, yield 68 %, HPLC purity 99.9, ESI + -MS 342 (100, [M+H] + ), 1 H-NMR (500 MHz, DMSO- d 6 ) δ (ppm): 3.92 (s, 2H, CH 2 C H 2 NHNBD), 4.46 (s, 2H, C H 2 CH 2 NHNBD), 6.44 (d, J = 8.3 Hz, 1H, NBD H6), 7.19 (s, 2H, NH 2 ), 8.04 (s, 1H, pur C2), 8.09 (s, 1H, pur H8), 8.46 (d, J = 8.9 Hz, 1H, NBD H5), 9.48 (s, 1H, CH 2 CH 2 N H NBD). 13 C-NMR (125 MHz, DMSO- d 6 ) δ (ppm): 41.3 ( C H 2 CH 2 NHNBD), 42.8 (CH 2 C H 2 NHNBD), 99.3 (NBD C6), 118.7 (pur C5), 121.3 (NBD), 137.7 (NBD C5), 141.0 (pur C8), 144.0 (NBD), 144.4 (NBD), 144.9 (NBD), 149.7 (pur C4), 152.3 (pur C2), 155.9 (pur C6).…”